• Product Description
  • Features
  • Product Configuration
  • Application Plan
  • Data Download
    • Commodity name: HCD28P/TSD Low Leakage Telephone (Red)

    HCD28P/TSD low-leakage telephone is a government-specialized telephone focusing on simplicity and practicality, classified as a commonly used wired communication terminal. It is mainly used for equipping military agencies and local party and government private networks. Suitable for program-controlled, automatic, and common battery telephone exchanges, it features good voice transmission quality, high reliability, lightning protection, and low electromagnetic leakage.

  • Main Functions

    Compatible with FSK/DTMF caller ID standards;

    Outgoing calls: up to 16 groups of 8 digits, dynamically stored internally, with a maximum storage length of 32 digits;

    Incoming calls: up to 52 groups of 8 digits, fully dynamically stored with single key and automatic IP;

    Three groups of 32-digit direct storage memory;

    Intelligent backlight;

    Incoming calls can be set as VIP function, deletion-proof, with special ringtone for incoming calls;

    24 diverse style ringtones, selectable ringtone volume;

    5-digit area code, 1-digit exit code, incoming call filtering;

    32-digit pre-dial and correction;

    Incoming and outgoing call callback;

    Automatic redial function;

    Hands-free volume adjustment;

    Music hold function;

    Incoming/outgoing numbers can be transferred to direct storage memory;

    Date, clock, and call timing functions;

    LCD brightness adjustment;

    32-digit last number redial;

    Number sending pause function;

    Flash function.

     

    Main Performance Indicators

    Operating Conditions

    Ambient temperature: -10℃ to 40℃

    Relative humidity: 10% to 95%

    Atmospheric pressure: 86kPa to 106kPa

    Ambient noise: ≤60dB(A)

     

    Main Technical Parameters

    Electroacoustic parameters (5km): Sending loudness rating (SLR) ≤15dB

    Receiving loudness rating (RLR) ≤2dB

    Sidetone masking rating (STMR) ≥12dB

    Stable balance return loss (2km): ≥15dB

    Echo balance return loss (2km): ≥17dB

    Sending and receiving nonlinear distortion: ≤7%

    DC resistance: ≤350Ω

    Ringing sound level: ≥70dB(A)

    Connection resistance: ≤350Ω

    Dual-tone multi-frequency signal level: Low frequency component -9dBm±3dB

    High frequency component -7dBm±3dB

    High frequency component level is 2dB ±1dB higher than low frequency component level

    Receiving caller ID information FSK signal:

    “0”=2200Hz±1% level is -37dBm to -6dBm

    “1”=1200Hz±1% level is -32dBm to -6dBm

    Level difference: ±10dB

    Mean Time Between Failures (MTBF): ≥5000h

    Power source: 3 AA batteries

    Dimensions: 228mm×180mm×105mm

  • HCD28P TSD.pdf

Keywords:

HCD28P/TSD Low Leakage Telephone (Red)

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